Aperçu du fichier PDF paralyses.pdf - page 6/16

Page 1 ... 4 5 678 ... 16

Aperçu du document


| Brain 2014: Page 6 of 16

C. Angeli et al.

Downloaded from by guest on April 8, 2014

Figure 3 Lower extremity EMG activity during voluntary movement occurred only with epidural stimulation in four individuals with motor
complete spinal cord injury. EMG activity during attempts of ankle dorsiflexion (A) without stimulation and (B) with stimulation. Force was
not collected for Patient B07. Electrode representation for each subject denotes the stimulation configuration used. Although stimulation
was applied throughout the time shown in B, in all four subjects EMG bursts were synchronized with the intent to move. Grey boxes are
cathodes and black boxes are anodes, white boxes are inactive electrodes. Stimulation frequency varied from 25 to 30 Hz. Muscles,
surface EMG: intercostal sixth rib (IC), tibialis anterior (TA), soleus (SOL); fine wire EMG: iliopsoas (IL), extensor digitorum longus (EDL),
extensor hallucis longus (EHL). Black bars represent flexion as determined by peak force generation and white bars represent passive
extension (from peak force to return to resting position). Although the subjects were instructed to flex and extend, they were unable to
actively extend before training. Grey highlighted indicates the active ‘flexion/extension’ period.

Reciprocity in the EMG activity of extensors and flexors when
flexing and extending the leg further indicates that the neural
activation specificity to the lumbosacral motor pools was sufficient
to generate a functionally coordinated movement (Fig. 4A and C).

When Patient A45 was asked to generate a sustained contraction
for ‘as long as possible’ the effort could be maintained for a few
seconds followed by several oscillatory movements (Fig. 4C).
There was alternating activity in the iliopsoas and vastus lateralis,

Ce fichier a été mis en ligne par un utilisateur du site. Identifiant unique du document: 00234478.
⚠️  Signaler un contenu illicite
Pour plus d'informations sur notre politique de lutte contre la diffusion illicite de contenus protégés par droit d'auteur, consultez notre page dédiée.